The present invention relates to a method and a device for fine or precision profiling or shaping tools which are coated with super-hard materials, for example cubic crystalline boron nitride or diamond, especially tools having a prescribed profile or shape and coated with a single layer.
In addition to metallic milling tools or cutters, ceramic profile grinding discs or wheels, which must be trued or sharpened frequently as a consequence of wear, are used to produce workpieces having a complicated external or internal shape or contour, especially toothing of gears. Sharpening or truing devices are employed for this purpose either separately or arranged on the machine; the sharpening or truing tools of these devices are made of a high-strength metal alloy or of diamonds.
Recently, grinding tools are being employed to an increasing extent which have a metallic foundation or main body which is coated or layered with a super-hard material, for example with cubic crystalline boron nitride or diamond. These tools have a very great accuracy or precision, and a long service life, so that up to now a truing was dispensed with.
In the event machining is to be performed at extremely high accuracy with a tool coated with a super-hard material, it is necessary to finely profile the cutting surface of such tools in order to remove those portions of the super-hard material which project from the true or desired profile. Such a fine or precision profiling is necessary, for example, if accuracy in the range of a few microns is to be achieved with a tool coated with super-hard material. Such a fine profiling of tools coated with super-hard material has up to now met with failure because the known sharpening or truing tools did not have a sufficient hardness for the shaping or profiling operation.
It is therefore an object of the present invention to provide a method and a device for fine profiling tools which are coated with a super-hard material and have a prescribed profile or shape, while maintaining a very high accuracy relative to the prescribed profile or shape in an economical and feasible manner.